Diabetes mellitus imposes a major burden on the public health of the United States, leading annually to over 300,000 deaths and over $130 billion in costs. This burden falls disproportionately upon ethnic minority groups, particularly African Americans, who are at excess risk for the development of type 2 diabetes and for a variety of its most serious complications. Suboptimal health care in terms of access, quality, and adherence, appears to be an important contributing factor. Over the past 5 years, the investigators have developed and tested a multi-faceted behavioral approach to enhance health care for urban African Americans with diabetes. In this approach, a Nurse Case Manager/Community Health Worker team works to identify and surmount barriers to optimal care on both the patient side (e.g., inadequate health knowledge, insufficient finances, distracting life events, non-adherence) and the primary care provider side (e.g., suboptimal monitoring or treatment of hyperglycemia, hypertension, or dyslipidemia). Preliminary analyses indicate that this intensive team approach, compared to usual care alone, produces substantial improvement in metabolic control, therefore offering the promise of health benefits 5-15 years hence. Yet however attractive the projected long-term benefits, economic realities compel managed care organizations to focus on actual benefits and costs in the short term, i.e., the two to four year interval which corresponds to both concrete financial planning and average duration of enrollment. Therefore, the investigators propose to conduct a randomized, controlled trial within a managed care organization to determine the effects of an Intensive Intervention (executed by a Nurse Case Manager/Community Health Worker team) on metabolic control, on the occurrence of diabetes-related health events and health care utilization, and on direct health care costs. The participants will be 800 African American adults with type 2 diabetes who receive primary care within a managed care organization in inner-city Baltimore, and who are at elevated risk for diabetic complications (e.g., suboptimal glucose or blood pressure control, missed primary care appointments, recent hospitalizations). The investigators hypothesize that within 3 years the up-front costs of the Intensive Intervention will be largely offset by savings related to reduced rates of ER visits, hospitalizations, and surgical procedures which result from improved metabolic control and other enhancements of primary care. If so, the investigators state that this project will provide strong evidence for the adoption of the Intensive Intervention locally and in other managed care organizations which provide care for high-risk urban minority populations. They further state that it would thereby contribute to nationwide efforts aimed a eradicating the excess risk of diabetic complications in African Americans and serve as a model for translational research related to other chronic medical conditions in minority populations.